A24-HASM-450 Digi International/Maxstream, A24-HASM-450 Datasheet - Page 36

• Manufacturer Part Number: A24-HASM-450
• Description: ANT 2.4GHZ DIPOLE HALF-WAVE
• Manufacturer: Digi International/Maxstream
• Series: XPressr

Specifications of A24-HASM-450

• Antenna Type: Whip: 1/2 Wave, Swivel, Tilt (Right Angle)
• Number Of Bands: 1
• Frequency: 2.4GHz
• Vswr: 2
• Gain: 2.1dBi
• Termination: RP-SMA
• Mounting Type: Connector
• Height (max): 4.35" (110.5mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 70000340; Q2724499B

XBee/XBee‐PRO ZigBee OEM RF Modules v1.x1x [2007.06.01]
6.0.2. API Types
Checksum
Modem Status
Data bytes that need to be escaped:
Note: In the above example, the length of the raw data (excluding the checksum) is 0x0002 and
the checksum of the non-escaped data (excluding frame delimiter and length) is calculated as:
0xFF - (0x23 + 0x11) = (0xFF - 0x34) = 0xCB.
To test data integrity, a checksum is calculated and verified on non-escaped data.
To calculate: Not including frame delimiters and length, add all bytes keeping only the lowest 8
bits of the result and subtract the result from 0xFF.
To verify: Add all bytes (include checksum, but not the delimiter and length). If the checksum is
correct, the sum will equal 0xFF.
Frame data of the UART data frame forms an API-specific structure as follows:
Figure 6‐08. UART Data Frame & API‐specific Structure:
The cmdID frame (API-identifier) indicates which API messages will be contained in the cmdData
frame (Identifier-specific data). Refer to the sections that follow for more information regarding
the supported API types. Note that multi-byte values are sent big endian.
API Identifier: 0x8A
RF module status messages are sent from the module in response to specific conditions.
Figure 6‐09. Modem Status Frames
Example - Raw UART Data Frame (before escaping interfering bytes):
0x11 needs to be escaped which results in the following frame:
0x7E 0x00 0x02 0x23 0x7D 0x31 0xCB
© 2007 Digi International, Inc.
• 0x7E – Frame Delimiter
• 0x7D – Escape
• 0x11 – XON
• 0x13 – XOFF
0x7E 0x00 0x02 0x23 0x11 0xCB
Start Delimiter
Start Delimiter
0x7E
(Byte 1)
0x7E
MSB
Length
LSB
MSB
API Identifier
(Bytes 2-3)
0x8A
Length
API-specific Structure
0 = Hardware reset
1 = Watchdog timer reset
2 = Joined
3 = Unjoined
6 = Coordinator started
LSB
Frame Data
API Identifier
cmdID
Identifier-specific Data
Status (Byte 5)
cmdData
API-specific Structure
Checksum
Frame Data
(Bytes 4- n)
1 Byte
Identifier-specific Data
cmdData
Chapter 6 ‐ API Operation
(Byte n + 1)
Checksum
1 Byte
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